The intercalation compound Li(Mn0.9Co0.1)O2 as a positive electrode for rechargeable lithium batteries

Abstract

By replacing only 10% of the Mn by Co in the layered lithium intercalation compound LiMnO₂ the amount of lithium that can be removed and reinserted is increased by 50% corresponding to an increase in the ability to store charge from 130 to 200 mA h g^–1 at 100 µ A cm^–2 and rendering this low cost/toxicity material of potential interest as a positive electrode in rechargeable lithium batteries; furthermore the cooperative Jahn–Teller distortion due to localised high spin Mn³⁺(3d⁴) in LiMnO₂ appears to be suppressed for Li_x(Mn_0.9Co_0.1)O₂; x<0.9 (80% Mn³⁺ assuming Co³⁺).